Chuck.



No. 884,244. PATENTED APR. 7, 1908. V. J. WAHLSTROM.

CHUCK.

APPLICATION FILED JULY 17. 1907.

Uivrrn sra rns Parnnr orrron.

VERNER J. WAI'ILSTROM, OF NEW YORK, N. Y.,ASSIG NOR OF ONE-HALF TOBERNHARD T. BURCHARDI, OF BROOKLYN, NEW YORK.

CHUCK.

To all whom it may concern:

Be it known that I, VERNER J. Warnr STROM, a citizen of the UnitedStates, residing at New York, in the county of Kings and State of NewYork, have invented a new and useful Chuck, of which the following is aspecification.

This invention relates to an improvement in chucks.

In certain types of chucks heretofore employed, a plurality of radiallymovable jaws has been used, each jaw carrying a roller arranged to berolled up an inclined face on the jaw by contact with a tool shank, toeffect the clamping of the same. In these devices, internal cam surfaceswere out upon a sleeve loosely mounted upon a chuckbody, the function ofthe cam surfaces being to produce, when rotated, a movement of the jawstoward the axis of the chuck. The rotation of the sleeve was effected bymeans of a spring.

It has been found in practice that by forming the cam surfaces upon thechuck-body itself and mounting the jaws in a relatively rotatable membercarried by the chuckbody, that a wider range is obtained, that is tosay, a larger number of different sized tool shanks may be clamped inthe device. This is due to the fact that the cam surfaces are positivelydriven and that there is, therefore, a constant tendency to crowd thejaws toward the aXis of the chuck, irrespective of the action of thespring that initially brings the jaws into contact with the tool shank.

It is one of the objects of this invention, therefore, to provide achuck in which the cam surfaces for moving the jaws inwardly are mountedon the chuck-body.

l/Vith this and other objects in View, the invention consists in certainconstructions and combinations which will be hereinafter fully describedand then specifically pointed out in the claims hereunto appended.

In the drawings which form a part of this specification and in whichlike characters of reference indicate the same parts, Figure 1 is anelevation, partly sectional, of a structure embodying the invention Fig.2 is a cross sectional view taken on the line 22 of Fig. 1; and Fig. 3is a cross sectional view taken on the line 33 of Fig. 1.

In carrying the invention into effect, there is provided a hollowchuck-body having a plurality of cam surfaces for operating the jaws andthis chuck-body may vary widely Specification of Letters Patent.

Application filed July 17, 1907.

Patented April 7, 1908.

Serial No. 384,251.

in construction. As shown, a hollow chuckbody 1 is employed and isconnected to a shank 2 by any suitable means, as for instance by aflange 3 formed integrally with the shank 2 and secured to thechuck-body by means of screws 1. In the device selected to illustratethe invention, internal cam surfaces 5 are formed on the chuck-body 1.

There is provided a relatively rotatable member carried by thechuck-body for supporting the jaws. As shown, a relatively rotatablemember 6 is mounted within the hollow chuck-body 1, before referred to,and is provided with a plurality of radial slots 7 in which are mounteda plurality of radially movable jaws 8, the rear ends of which contactwith the cam surfaces 5, before referred to. Each of the jaws 8, carriesa gripping roller 9 mounted therein in a manner well known in the art.The upper end of the rotatable member 6 contacts with a boss 10 eX-tended from the shank 2, before referred to, and is held in positionwithin the chuckbody 1 by means of a plate 11 secured to the chuck-body1 by suitable means, as screws 12.

A spring 13, one end of which is fixed in the flange 3 and the other tothe rotatable member 6, is provided for the purpose of producing arelative movement of the chuckbody and member to cause the jaws toapproach the aXis of the chuck.

Means are provided for positively producing a reverse movement and thismeans may vary widely in construction. As shown, the rotatable member 6is rovided near its lower end, with a segmenta rack 14 which is in meshwith a pinion 15 loosely mounted in the chuckbody 1 and retaining plate11. A sleeve 16 is rotatably mounted upon the lower end of thechuck-body 1, and this sleeve is provided with a segmental rack 17, inmesh with the pinion 15, before referred to.

In the operation of the device, the shank 2 is inserted in a drillpress, and through its connections the chuck-body 1 is positivelydriven. When a tool shank is inserted in the central aperture of thechuck between the gripping rollers 9, the spring 13 will produce a reative movement of the chuck-body 1 and member 6 to cause the jaws tomove toward the axis of the chuck. While the tool shank is held inposition, there is a constant tendency of the positively driven camsurfaces 5, to move the jaws inwardly with a force greatly in excess ofthat exerted by the spring 13 during the initial inward movement of thejaws. Owing to this construction and action, the cam surfaces 5 may besteeper than in constructions heretofore used and the range of the chuckthereby increased. To release the tool, the sleeve 16 is grasped by theoperative and stopped, which results in the rotation of the pinion 15and a reverse movement of the member 6, this movement relieving the jawsfrom the force exerted by the cam surfaces 5. The tool will then fall,or may be readily slipped out.

Changes and variations may be made in the structure by which theinvention is carried into effect. The invention, therefore, is

not to be limited to the precise details of the structure shown anddescribed.

What is claimed is:

In a chuck, the combination with a chuckbody provided with a pluralityof cam surfaces, a relatively rotatable jaw carrying member mountedtherein, a segmental rack formed on said member, a pinion carried by thechuck-body and in mesh with said rack, and a sleeve rotatably mounted onthe chuckbody and having a segmental rack in mesh with the pinion,substantially as described.

In testimony whereof, I have signed my name to this specification in thepresence of two subscribing witnesses.

VERNER J. lVAHLSTROM.

Witnesses J. D. H. BERGEN, H. C. GUIoN.

